Question: 4 glue sticks cost $4.56. Which equation would help determine the cost of 6 glue sticks?
There are several equations that could help determine the cost, each with a slightly different approach. We know the cost of 4 glue sticks. We want to know the cost of 6 glue sticks. We can write the numbers of glue sticks as a proportion: $\dfrac{4}{6}$ We know 4 glue sticks costs $4.56. We can let $x$ represent the unknown cost of 6 glue sticks. The proportion of these costs can be expressed as: $\dfrac{\$4.56}{x}$ The cost changes along with the number of glue sticks purchased, and so the two proportions are equivalent. $\dfrac{4}{6} = \dfrac{\$4.56}{x}$